Steam-engine



(No Mudel.) 2 Sheets-Sheet 1.

E. P. PEAGOGK. STEAM ENGINE. No. 497,987. Patented My 23, 1893.

T. 1h? j I i I Z? I 2 Sheets-Sheet 2.

K O 0 O A E P F B a d 0 M 0 w STEAM ENGINE.

Patented May 23, 1893.

1 I I i l I llllll Ill linrrno STATES PATENT OFFICE,

EDWARD FRANKLIN PEACOCK, OF PHILADELPHIA, PENNSYLVANIA.

STEAM-ENGINE.

SPECIFICATION forming part of Letters Patent No. 497,987, dated May 23,1893.

Application filed June 27, 1892. SerialNo. 438,124. (No model.)

T0 at whom it may concern.-

Be it known that I, EDWARD FRANKLIN PEA- OOCK, a citizen of the UnitedStates, residing at Philadelphia, in the county of Philadelphia andState of Pennsylvania, have invented certain new and useful Improvementsin Steam-Engines; and I do declare the following to be a full, clear,and exact description of the invention, such as will enable othersskilled in the art to which it appertains to make and use the same,reference being had to the accompanying drawings, and to the letters ofreference marked thereon, which form a part of this specification.

My invention relates to steam engines, and its objects are to rendertheir operation more economical, to reduce the strain and wear on thecrank pin, and valve, to prevent the valve from tilting up when workingat full stroke and so permitting steam to escape, and in other ways toimprove the operation of the machine.

The invention is applicable to any class of steam engines, but I shalldescribe and illustrate it as embodied in a locomotive, for which it isespecially adapt-ed.

The invention consists in means for varying the size of the steam ports;and means for bridging a portion of the admission ports to prevent theincoming steam from lifting the end of the valve.

In the accompanying drawings, Figure 1 is a side elevation, partlybroken away, of a steam engine cylinder equipped with my improvements.Fig. 2 is a cross section. Fig. 3 is a plan of the valve seat. Fig. atis a modification. Fig. 5 is a view of the connecting link. Fig. 6 is aplan of the balance ring.

The ordinary locomotive cylinder A shown in the drawings usually haslong steam ports a, and exhaust ports a, in order to admit and exhaustthe steam quickly.

When applying my invention to old engines, I provide a false valve seatB, containing ports I) 1; adapted to register in width with the ports 0ba, but considerably shorter in length. The valve 0 is madecorrespondingly narrower, andis guided between flanges on the valveseat. I prefer to make these flanges in the shape of boxes 11 in orderto fill a portion of the steam space. The false .ings G.

valve seat is held upon the cylinder by set screws I) which are tappedthrough the cover E of the valve chest and bear upon the tops of theboxes 19 or upon the short columns 11 rising therefrom. A jam-nut (Zlocks each set screw. In order to still further reduce the effectivearea of the steam ports, and to render them adjustable in size, a slidevalve F is provided at one or both ends of each steam port.

Any other device capable of answering the purpose may be used, andthough I prefer a slide, I do not limit myself thereto. These valves maybe operated in any suitable manner, either singly or together.

In the drawings, each slide F moves in a groove 1), cut transversely inthe false valve seat B, and coinciding with a steam port I). The outerend of the slide has a flange or lug f, to which is attached a stem Fwhich reciprocates in a tubular guide 12 projecting from the box I)through the side of the valve chest. A packing ring f makes the stemsteam tight. Theouter end of the stem is jointed to a rock arm 9 on arock-shaft G, running along the side of the valve chest, and supportedin bear- At one end of each shaft is an arm g, the two arms beingpreferably connected by a link H, which may be bent to clear the valverod 0. Since one arm g extends above its shaft, and the other below, theslides F g are all moved outward or inward simultaneously. When moved into their full extent, the area of the portsb is reduced one half asshown in Fig. 3; or to a greater or less amount, as desired.

The rock shafts may be operated by hand; or, if desired, they may beconnected with the reversing lever so that when the valve is working atfull stroke the slide will be properly adjusted.

The valve 0 is preferably made in the two parts, to wit: a body, and aseparate face 0 attached to the body by rivets c, which are preferablytapering, the larger end being outermost, so that in case a rivet getsloose it valve carries a cylindrical boss 0 preferably integral with thebody of the valve. A shallow cylindrical ring I fits nicely over theboss 0 the joint being made steam tight by a pack ing ring 0 sprung intoa groove, preferably in the periphery of the boss, as shown. A cross-bar9; extends diametrically across the ring, and carries on its under sidea pocket 6 in which is held a spring K, resting on top of the valve, andkeeping the ring pressed up snugly against the top of the valve chest.The top of the valve inside the ringis thus shut off from the pressureof the steam in the chest, and to this extent the valve is balanced. Thecircular shape of the ring permits it to revolve around the boss, andthus Wear evenlyand keep a tight joint, where it comes in contact withthe balance plate or the chest lid. 7

Then a slide valve Works at full stroke, it runs over the ends of thevalve seat and overlaps the admission ports. The incoming steam liftsthe valve, and a portion of it escapes through the exhaust port.Moreover, the valve is caused to wear unevenly. To

obviate this, I extend the false valve seat 13' over the admission portsL forming a bridge B for the valve, to travel on, and compelling thesteam to enter the chest through the spaces shown inclosed in dottedlines in Fig. 3. In new work, these bridges can be cast integral withthe valve seat. 80, too, in new engines, the ports can be made short andthe false valve seat dispensed with, the grooves for the slides F beingcored or planed out in the valve seat.

Instead of the columns b being cast integral with the boxes 12 they maybe separate studs b screwed down through suitable holes into thevalveseat, as shown in Fig. 4. I do not however, make any claim in thisapplication to the means above described for balancing the valve, sincethis constitutes a separate invention reserved for another application.

Having thus described my invention, what I claim, and desire to secureby Letters Patcut, is

1. A false valve seat having ports to register with those of a steamengine cylinder, and having slides adapted to vary the size of saidports, and means for adjusting said slides independently of the valvemotion substantially as set forth.

2. A false valve seat, having ports to register with those of a steamengine cylinder, and having transverse grooves in linewith said ports,slides reciprocating in said grooves, and means for adjusting saidslides independently of the valve motion substantially as set forth.

3. The combination with a cylinder and valve chest, of a false valveseat having ports shorter than those in the valve seat, side flangesadjacent to the ends of said ports, and a valve fitted between saidflanges, substantially as set forth.

4:. The combination with a cylinder and valve chest, of a false valveseat having boxes on each side, a valve guided between said boxes, andslides operating transversely in said boxes, to vary the effective areaof the ports, substantially as set forth.

5. The combination with a cylinder and valve chest, of a false valveseat B having boxes 5 and grooves 12 slides F in said grooves, stems Fattached to said slides and projecting outside of said chest, and rockshafts G connected with said stems and with each other, substantially asset forth.

6. A valve comprising an upper part and a separate Valve face unitedthereto by taper ing rivets having their larger ends outermost,substantially as set forth.

7. A steam engine having a bridge across the admission ports, to thevalve chest to prevent the incoming steam from tilting the valve,substantially as set forth.

8. The combination with asteam engine cylinder, of a false valve seathaving at each end an extension to bridge the admission ports,substantially as set forth.

In testimony whereof I affix my signature in presence of two witnesses.

EDWARD FRANKLIN PEACOCK.

lVitnesses:

W. W. FERGUSON, JOSEPH THOMASSON.

